DOI10.47051/YRFI9484

Published November 2, 2020. Updated November 30, 2023. Open access. Peer-reviewed.

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Raney’s Lightbulb-Lizard (Riama raneyi)

Reptiles of Ecuador | Sauria | Gymnophthalmidae | Riama raneyi

English common name: Raney’s Lightbulb-Lizard.

Spanish common name: Lagartija minadora de Raney.

Recognition: ♂♂ 18.8 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=8.2 cm. ♀♀ 16.9 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=8 cm..1–3 Lightbulb-lizards are easily distinguishable from other lizards by their fossorial habits and extremities so short that the front and hind limbs cannot reach each other.1,2 Riama raneyi is one of four members of its genus known to occur along the Amazonian slopes of the Andes in northeastern Ecuador. Riama raneyi differs from the other three species (R. anatoloros, R. orcesi, and R. simotera) by lacking dorsolateral stripes and by having only one superciliary scale (Fig. 1).2 Adult males differ from females by being larger, more colorful, and having broader heads.

Variation among individuals of Riama raneyi

Figure 1: Individuals of Riama raneyi from El Carmelo–Santa Bárbara road, Sucumbíos province, Ecuador. j=juvenile

Natural history: Riama raneyi is a rarely seen fossorial lizard that inhabits old-growth to heavily disturbed high evergreen montane forests. It also occurs in areas containing a mixture of pastures, crops, rural houses, and remnants of native vegetation.3 Raney’s Lightbulb-Lizards spend most of their lives in tunnels they excavate in areas of soft soil, in dirt walls, or under rocks and logs,3 but they have also been seen moving at ground level during the day.3 Females lay clutches of 2–3 eggs in communal nesting sites such as under rocks.2,3 As many as 8–24 eggs have been found in these sites, and females occasionally coil around the eggs, presumably protecting them.2,3 When dug up or otherwise exposed, these shy reptiles will quickly flee under cover. If captured, they may bite or readily shed the tail. Raney’s Lightbulb-Lizards are susceptible to high temperatures, dying if exposed to the sun or even if handled for longer than just a few seconds.3 A Roadside Hawk (Rupornis magnirostris) was seen preying upon an individual of R. raneyi.4 Members of this species can be found living alongside individuals of R. orcesi in the valley of the Papallacta river.2 Differences like larger body size, but comparatively shorter limbs in R. raneyi could be allowing the coexistence between the two species by influencing the use of different microhabitats.2

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Conservation: Least Concern Believed to be safe from extinction given current circumstances.. Riama raneyi is listed in this category, instead of Vulnerable,5,6 because the species occurs in three major protected areas (Antisana Ecological Reserve, Cayambe Coca National Park, and Sumaco National Park) and it is distributed over an area that retains the majority (~91.7%) of its forest cover.7 Therefore, the species is here considered to be facing no major immediate extinction threats.

Distribution: Riama raneyi is endemic to an area of approximately 4,313 km2 along the Amazonian slopes of the Andes of northern Ecuador (Fig. 2). The species has not been recorded in southern Colombia, but its presence in this country has not been confirmed.

Distribution of Riama raneyi in Ecuador

Figure 2: Distribution of Riama raneyi in Ecuador. The star corresponds to the type locality: Cuyuja, 3.3 km ESE of*, Napo province. See Appendix 1 for a complete list of the presence localities included in the map.

Etymology: The generic name Riama does not appear to be a reference to any feature of this group of lizards, but a matter of personal taste. John Edward Gray usually selected girls’ names to use on reptiles.8–11 The specific epithet raneyi honors Richard Raney, of Lawrence, Kansas, in recognition of his generous support towards the research that led to the discovery of this lizard species.2

See it in the wild: Raney’s Lightbulb-Lizards are recorded rarely unless actively searched for by digging in areas of soft soil in pastures adjacent to the forest border. The region having the greatest number of recent observations is the environs of the town El Carmelo, Carchi province.

Acknowledgments: Special thanks to Amanda Quezada, Harry Turner, and Frank Pichardo for finding the specimens of Riama raneyi pictured in this account. Thanks to Frank Pichardo for providing natural history data of R. raneyi. Thanks to Amanda Quezada for the post-processing of images. This account was published with the support of Secretaría Nacional de Educación Superior Ciencia y Tecnología (programa INEDITA; project: Respuestas a la crisis de biodiversidad: la descripción de especies como herramienta de conservación; No 00110378), Programa de las Naciones Unidas (PNUD), and Universidad San Francisco de Quito (USFQ).

Authors: Alejandro ArteagaaAffiliation: Khamai Foundation, Quito, Ecuador.

Academic reviewer: Jeffrey D CamperbAffiliation: Department of Biology, Francis Marion University, Florence, USA.

Photographer: Jose VieiracAffiliation: Tropical Herping (TH), Quito, Ecuador.,dAffiliation: ExSitu, Quito, Ecuador.

How to cite? Arteaga A (2023) Raney’s Lightbulb-Lizard (Riama raneyi). In: Arteaga A, Bustamante L, Vieira J (Eds) Reptiles of Ecuador: Life in the middle of the world. Available from: www.reptilesofecuador.com. DOI: 10.47051/YRFI9484

Literature cited:

  1. Galarza-Verkovitch D (2020) Riama raneyi. In: Torres-Carvajal O, Pazmiño-Otamendi G, Ayala-Varela F, Salazar-Valenzuela D (Eds) Reptiles del Ecuador. Museo de Zoología, Pontificia Universidad Católica del Ecuador. Available from: https://bioweb.bio
  2. Kizirian DA (1996) A review of Ecuadorian Proctoporus (Squamata: Gymnophthalmidae) with descriptions of nine new species. Herpetological Monographs 10: 85–155. DOI: 10.2307/1466981
  3. Field notes, Reptiles of Ecuador book project.
  4. Frank Pichardo, pers. comm.
  5. Cisneros-Heredia DF, Valencia J, Almendáriz A, Brito J (2019) Riama raneyi. The IUCN Red List of threatened species. Available from: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2019-3.RLTS.T50950543A50950550.en
  6. IUCN (2001) IUCN Red List categories and criteria: Version 3.1. IUCN Species Survival Commission, Gland and Cambridge, 30 pp.
  7. MAE (2012) Línea base de deforestación del Ecuador continental. Ministerio del Ambiente del Ecuador, Quito, 30 pp.
  8. Gray JE (1831) Description of a new genus of ophisaurean animal, discovered by the late James Hunter in New Holland. Treuttel, Würtz & Co., London, 40 pp.
  9. Gray JE (1831) A synopsis of the species of the class Reptilia. In: Griffith E, Pidgeon E (Eds) The animal kingdom arranged in conformity with its organization. Whittaker, Treacher, & Co., London, 1–110.
  10. Gray JE (1838) Catalogue of the slender-tongued saurians, with descriptions of many new genera and species. Annals and Magazine of Natural History 1: 274–283.
  11. Gray JE (1845) Catalogue of the specimens of lizards in the collection of the British Museum. Trustees of the British Museum, London, 289 pp.

Appendix 1: Locality data used to create the distribution map of Riama raneyi in Ecuador (Fig. 2). Go to the section on symbols and abbreviations for a list of acronyms used. Asterisk (*) indicates type locality.

CountryProvinceLocalitySource
EcuadorCarchiEl Carmelo, 6 km NW ofKizirian 1996
EcuadorCarchiJulio Andrade–El CarmeloReptiles of Ecuador book database
EcuadorNapoCordillera de GuacamayosKizirian 1996
EcuadorNapoCuyujaKizirian 1996
EcuadorNapoCuyuja, 3.3 km ESE of*Kizirian 1996
EcuadorNapoSumaco camp 2Reptiles of Ecuador book database
EcuadorSucumbíosJulio Andrade, 32 km E ofThis work; Fig. 1
EcuadorSucumbíosNear La AlegríaKizirian 1996
EcuadorSucumbíosNear Santa BárbaraSánchez-Pacheco et al. 2012
EcuadorSucumbíosSanta Bárbara, 18 km E ofKizirian 1996